CVE-2026-53904Network attack vector

Account lockout via unlimited password resets

Published Jul 1, 2026 · Updated Jul 1, 2026

Account denial of service in MyComplianceOffice MCO 25.3.3.1 allows remote attackers to lock users out through password resets. The password-reset flow invalidates the current password and previously issued temporary passwords on every successful request without limiting repeated resets. A victim's email address and correct security-question answer are required; limited answer attempts constrain guessing, but repeated valid resets keep the account inaccessible.

CVSS severity6.3
Medium
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Account denial of service in MyComplianceOffice MCO 25.3.3.1 allows remote attackers to lock users out through password resets. The password-reset flow invalidates the current password and previously issued temporary passwords on every successful request without limiting repeated resets. A victim's email address and correct security-question answer are required; limited answer attempts constrain guessing, but repeated valid resets keep the account inaccessible.

The record

CVE
CVE-2026-53904
Published
Jul 1, 2026
Updated
Jul 1, 2026
Vendor
MyComplianceOffice
Product
MCO
Classifications
CWE-307, CWE-640, CAPEC-2, T1531
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 1, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=25.3.3.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

MyComplianceOffice · MCOversion=25.3.3.1

Published CVSS scores

7.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
6.3CERT.PLCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-307Improper Restriction of Excessive Authentication Attempts
CWE-640Weak Password Recovery Mechanism for Forgotten Password
CAPEC-2Inducing Account Lockout
T1531Account Access Removal

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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